adding nc2schemaorg function

Author: jyucsiro

nc2rdf/bald2schemaorg_mappings.json

@@ -0,0 +1,8 @@
+[
+   { "bald" : "summary", "schemaorg": "description" }, 
+   { "bald" : "title", "schemaorg": "name" }, 
+   { "bald" : "id", "schemaorg": "identifier" }, 
+   { "bald" : "keywords", "schemaorg": "keywords" }, 
+   { "bald" : "license", "schemaorg": "license" }, 
+   { "bald" : "standard_name", "schemaorg": "variableMeasured" }
+]

nc2rdf/nc2rdf.py

@@ -5,14 +5,79 @@
 import netCDF4
 import numpy as np
 import bald
+import rdflib
+import json
+from rdflib import Namespace, BNode, URIRef, Literal
+from rdflib.namespace import RDF
+
+
+
+def getBasename(urlstr):
+   return os.path.basename(urlstr)
+
+def baldgraph2schemaorg(graph):
+    """
+       Input: netCDF file
+       Transforms to a rdflib.Graph bald style
+       Returns a new graph in schema.org profile
+    """
+    #load mappings
+    mapping_idx = {}
+    mapping_data = []
+    with open('bald2schemaorg_mappings.json' , 'r') as f:
+       mapping_data = json.load(f)
+       
+    for item in mapping_data:
+       mapping_idx[item['bald']] = item['schemaorg']
+
+    qres = graph.query(
+    """PREFIX bald: <http://binary-array-ld.net/latest/> 
+       SELECT DISTINCT ?pred ?value
+       WHERE {
+          ?c a bald:Container .
+          ?c ?pred ?value
+       }""")
+ 
+    schema_g = rdflib.Graph()
+    container = BNode()
+    so = Namespace("http://schema.org/")
+    schema_g.add( (container, URIRef("http://www.w3.org/1999/02/22-rdf-syntax-ns#type"), so.Dataset) )
+
+    for row in qres:
+       currField = getBasename(str(row[0])).strip()
+       #print(getBasename(str(row[0])) + ' (type: ' + str(type(row[0])) + ")" + " :: " + row[1] + ' (type: ' + str(type(row[1])) + ")")
+       if(currField in mapping_idx.keys()):
+          print('schemaorg:' + mapping_idx[currField], "\t", row[1])
+          predUri = URIRef("http://schema.org/" + mapping_idx[currField])
+          lit = Literal(row[1])
+          schema_g.add( (container, predUri, lit) )
+    return schema_g
+
+def nc2schemaorg(ncfilename, outformat, baseuri=None):
+    root_container = bald.load_netcdf(ncfilename, baseuri=baseuri)
+    graph = root_container.rdfgraph()
+    schema_g = baldgraph2schemaorg(graph)
+    
+    if(outformat == 'json-ld'):
+       context = "http://schema.org/"
+       s = schema_g.serialize(format=outformat, context=context, indent=4).decode("utf-8")
+    else:
+       s = schema_g.serialize(format=outformat).decode("utf-8")
+    print(s)
 
 def nc2rdf(ncfilename, outformat, baseuri=None):  
-    #print("nc2rdf test")
-    #print(ncfile)
     root_container = bald.load_netcdf(ncfilename, baseuri=baseuri)
     ttl = root_container.rdfgraph().serialize(format=outformat).decode("utf-8")
     print(ttl)
 
+def cdl2schemaorg(cdl_file, outformat, baseuri=None): 
+    tfile, tfilename = tempfile.mkstemp('.nc')
+    subprocess.check_call(['ncgen', '-o', tfilename, cdl_file])
+    schema_g = nc2schemaorg(tfilename, outformat, baseuri=baseuri)
+    os.close(tfile)
+    os.remove(tfilename)
+    return schema_g
+
 def cdl2rdf(cdl_file, outformat, baseuri=None): 
     #print("cdl2rdf test")
     #print(cdl_file)
@@ -32,13 +97,20 @@ def cdl2rdf(cdl_file, outformat, baseuri=None):
     parser.add_argument('--baseuri', action="store", dest="baseuri", help="Base URI for the graph")
     parser.add_argument('--cdl', action="store_true", dest="isCDL", default=False, help="Flag to indicate file is CDL")
     parser.add_argument('--nc', action="store_true", dest="isNC", default=False, help="Flag to indicate file is netCDF")
+    parser.add_argument('--schema-org', action="store_true", dest="isSchemaOrgOutput", default=False, help="Flag to indicate if schema.org output activated")
     parser.add_argument("ncfile", help="Path for the netCDF file")
 
     args = parser.parse_args()
 
     if(args.isCDL or args.ncfile.endswith(".cdl") or args.ncfile.endswith('.CDL')):
-        cdl2rdf(args.ncfile, args.format, baseuri=args.baseuri)
+        if(args.isSchemaOrgOutput):
+           cdl2schemaorg(args.ncfile, args.format, baseuri=args.baseuri)
+        else:
+           cdl2rdf(args.ncfile, args.format, baseuri=args.baseuri)
     elif(args.isNC or args.ncfile.endswith(".nc") or args.ncfile.endswith('.NC')):
-        nc2rdf(args.ncfile, args.format, baseuri=args.baseuri)
+        if(args.isSchemaOrgOutput):
+           nc2schemaorg(args.ncfile, args.format, baseuri=args.baseuri)
+        else:
+           nc2rdf(args.ncfile, args.format, baseuri=args.baseuri)
     else:
         print("Unrecognised file suffix. Please indicate if CDL or NC via --cdl or --nc");